Range of motion control device

ABSTRACT

A device for controlling range of motion of a stack of weights of a pin selectorized strength machine. First and second assemblies of the device are sized and dimensioned respectively for insertion into a hole of a weight selector stem of a pin selectorized strength machine, and for clamping to a guide rod. Methods of using the device.

FIELD OF THE INVENTION

The present invention relates to devices which limit the range of motion of weight stacks in exercise machines. In particular, the device limits the range of motion on weight-lifting machines using selectorized variable-resistance.

BACKGROUND

A class of resistance exercise devices incorporates a plurality of stacked weights providing resistance to the movement of a user's arms, legs, torso, or neck. In a selectorized weight lifting apparatus, a plurality of weights are nested together, and mechanisms for selecting an amount of weight which the user moves through a range of motion (ROM). Typically, selectorized weight machines use a cam weight transfer mechanism to limit the range of motion (Cybex, Inc.) Prior ROM limiting mechanisms have utilized the weight transfer cam, and a series of holes with a pull pin adjustment, and are specific to the machines. The “selectorized” aspect of selectorized variable-resistance exercise machines allows the user to select how many weight plates from a weight stack the user wishes to lift for a particular exercise. The user chooses a desired number of plates is typically by inserting a pin into a hole in one of the plates. Selectorized variable-resistance weight machines are well known in the commercial industry, for example, those prior models made by CYBEX International, Inc. and Nautilus Sports.

Certain users of selectorized weight machines have limitations which restrict their arms, legs, torso or neck from a full range of motion. For rehabilitation, it is often important to limit the range of motion for the patient. Rehabilitation patients and elderly would benefit from a device that would allow control of both start and terminal range of motion on all selectorized variable-resistance weight machines. ROM limitation mechanisms would also be useful in exercise and training

Selection of the correct start and stop point in the range of motion is critical to prevent injury. Sports medicine and rehabilitation physicians and physical therapists have long recognized that there are certain safe ranges of motion for rehabilitation for certain injuries, and that the use of selectorized variable-resistance exercise machines can aid in rehabilitation within the critical range limits.

Virtually all weight equipment manufacturers make machines for “healthy normals”, who do not require ROM controls.

Presently, the only way to control ROM is to use or buy machines with integrated ROM limits, available only from a few manufactures, and at considerable cost. There are no portable, independent ROM devices that can be used in conjunction with strength machines.

It would be advantageous for clinicians to have machines with the ability to “dose” a range of motion to their patients/clients. It would be preferable to have a device that easily and reversibly converts a selectorized weight machine into one which is appropriate for individuals who additionally require or prefer an exercise device with a controlled range of motion.

These shortcomings are resolved by the present invention which provides rehabilitation and exercise professionals with a simple tool to limit the range of motion both at start and terminal points. The device of the present invention adapts for use with most commercially available pin-selectorized weight-stack machines, and provides safe use of equipment which otherwise would be deemed inappropriate for the application.

SUMMARY

The present invention provides a device for controlling range of motion of a stack of weights in a pin selectorized strength machine (PSSM). The device comprises two assemblies. A first assembly is sized and dimensioned for laying on the top surface of a weight plate. The first assembly comprising a planar body. A protrusion extends from one end of the first assembly, the protrusion sized and dimensioned for insertion into a hole of a weight selector stem. A second assembly comprises a clamp which is sized and dimensioned for attachment to a guide rod.

The invention includes a method of using the range of motion control device of the invention for dosing a range of motion on a pin selectorized strength machine. The method comprises the steps of clamping a second assembly, which is a terminal limit range of motion controller, thereby establishing a terminal limit of motion. Another step comprises insertion of the weight selector pin of a first assembly, that is, a start limit assembly into a hole of the weight selection stem mechanism. This step achieves limiting vertical movement of the weight selector stem mechanism, thereby establishing a start limit of motion.

Another aspect of the invention is a pin selectorized strength machine in combination with the range of motion control device. Accordingly, the invention is directed to a PSSM comprising a first assembly sized and dimensioned for laying on the top surface of a weight plate, the first assembly comprising a planar body having a thickness and a protrusion extending from one end of the planar body. The protrusion is sized and dimensioned for insertion into a hole of a weight selector stem mechanism. The PSSM further includes a second assembly comprising a clamping mechanism sized and dimensioned for attachment to a guide rod of said pin selectorized strength machine.

Still another aspect of the invention discloses a method for dosing a range of motion of a selected stack of weight plates of a pin selectorized strength machine. The method comprises the steps of clamping a terminal limit assembly for controlling range of motion on the guide rod thereby establishing a terminal limit of motion; and insertion of the weight selector pin of a start limit assembly of said device into the hole of the weight selection stem mechanism, thereby establishing a start limit of motion.

An embodiment of the invention is directed to a kit which comprises at least one device of the invention (i.e. a start assembly and a terminal assembly). An aspect of the kit further includes one or more pin selectorized strength machines.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a typical weight stack of a pin selectorized strength machine (PSSM.) with the two assemblies of the device installed.

FIG. 2 is a view of FIG. 1 showing a pin selector inserted through a weight plate and engaged in the weight selector stem mechanism in the weight stack below the first assembly of the device of the invention. The terminal assembly is clamped on a guide rod above the top plate, the start assembly positioned on the top weight plate of a selected stack of weight plates, the start assembly inserted into a hole of the weight selector stem mechanism.

FIG. 3 is a side sectional view of the weight stack showing the first assembly atop the top weight plate of the stack of weight plates. The terminal assembly is clamped on a guide rod above the top plate. The pin selector is positioned below the top weight plate, both the first assembly and the pin selector engaged in respective holes of the weight selector stem mechanism.

FIG. 4 shows the protrusion of a start point limit assembly engaged in a hole of the weight selector stem mechanism, which is illustrated in ghost.

FIG. 5 is a top side perspective view of the start assembly.

FIG. 6 is a perspective view of the terminal assembly clamped onto the ghost of a guide rod.

FIG. 7 is a bottom perspective view of the terminal assembly.

FIG. 8 shows dimensions of an embodiment of a first assembly.

FIG. 9 shows dimensions of an embodiment of a second assembly.

DETAILED DESCRIPTION

The present invention is device that allows quick and easy controlled range of motion (ROM) dosing on virtually all commercially available pin selectorized strength machines (PSSM). The invention is detachable from a PSSM, and can be used in combination with other PSSMs.

In use, the device in combination with a PSSM provides users, clinicians, and rehabilitation, and exercise professionals the ability to dose a range of motion for their patients/clients. In operation, the device limits the range of motion both at inception and terminal points of exercise, inception alone, or terminal alone. This invention provides safe use of equipment which otherwise would be deemed inappropriate for the application.

As best seen in FIGS. 1 and 2, a typical PSSM includes a conventional weight stack for providing resistance to a user's movement of an input assembly. The weight stack is operatively and selectively connected to one end of a tether or cable by inserting a pin in one of the holes of the weight plates of a selected stack as is well known in the art. FIG. 3 shows the pin sufficiently inserted to engage, as well, in the cognate hole of the weight selector stem mechanism, thereby linking the selected stack of weights to the weight selector stem mechanism, which depends from the bottom surface of the top plate. The tether extends up from the top plate, and an intermediate portion of tether extends over pulleys to an input assembly.

A starting point is determined by the user inserting the protrusion of the start point assembly into a hole in the partially exposed weight selector stem mechanism. Accordingly, when a start point assembly is engaged with the weight selector stem mechanism, the downward travel of the weight selector stem mechanism is obstructed by the engaged start point assembly, thereby achieving a starting position for the range of movement.

Should the user desire to add weight to the resistance, the selector pin of the PSSM is inserted in a desired weight plate into engagement with the weight selector stem mechanism at a position below the start assembly's engagement with the weight selector stem mechanism.

Simultaneously, a terminal limit assembly of the device placed in clamped fixation to a guide rod thereby achieving the ending position for the range of movement. The ending position is also referred to herein as the terminal ROM limit. Accordingly, use of the device of the invention allows the exerciser to adjust the start and stop positions through an allowable or specifically dosed adjustment range. Thus, a method of adjusting the start and stop positions of the range of motion is achieved by a method comprising the steps: (a) selection of a vertical position on the guide rod for clamping the terminal limit assembly and (b) placement of the start limit assembly on top of the top weight plate of a selectorized nested stack of weight plates and insertion of a weight selector pin shaped as a protrusion of the start assembly into the corresponding hole of the weight selection stem mechanism. Either start or terminal ROM limits may be used alone, or in conjunction.

In FIGS. 1, 2 and 3, the start point assembly is depicted laying on the top surface of the top weight plate of a selected stack of plates, and inserted into the cognate hole of the weight selector stem mechanism. Should the user desire to add weight to the resistance, the PSSM's selector pin is inserted into the stem mechanism below the position of the starting assembly, thereby “nesting” a stack of weight plates.

FIGS. 1 and 2 illustrate the terminal limit assembly, clamped on a guide rod. The terminal ROM limit is achieved by the terminal assembly obstructing the upward movement of the upper weight plate along the guide rod at the level the user wishes to terminate the movement.

Accordingly, the device combined with the weight stack guide rod and top plate and weight selector stem assembly achieves both start and terminal range limits on the user's motion.

FIGS. 1 and 2 show a typical weight-stack of a pin selectorized strength machine (PSSM) with the two assemblies of the device installed. The weight-stack is the resistance aspect of most selectorized strength-training equipment. The weight-stack consists of an outer frame [1] that supports two guide rods [3] and a series of iron or steel weight plates [5] that slide up and down on the guide rods. The weights are pulled up by the person using an input assembly via a tether or cable [7] that is connected to a specially adapted weight plate [9] sometimes called a “top-plate” from which depends a weight selector stem mechanism[11]. The selector stem mechanism has a series of holes (60) that line up with corresponding holes, i.e. cognate holes, in the weight plates [5] when the machine is at rest. The person who operates the input assembly of the machine uses the PSSM's selector pin [13] (FIGS. 2 and 3) to change the weight they are going to lift by inserting the selector pin into the desired weight-plate and into inserted engagement with the respective hole of the stern mechanism, thereby coupling a desired number of weight plates to the stem mechanism. Positioned on the top weight plate of the stack of weight plates, the start point limit assembly [15] is shown insertingly engaged into one of the holes of the weight selector stem mechanism [11]. The terminal limit assembly [17] is shown clamped onto one of the guide rods above the top-plate[9].

FIGS. 4 and 5 show an embodiment of the start point limit assembly [15], which comprises a substantially planar body having a thickness and an upper and lower surface bounded by edges and walls. A protrusion or weight selector pin extends from an end of the assembly. The distal region of the protrusion is sized and shaped for insertion into a hole of the weight selector stem mechanism. At the other end of the assembly, an embodiment has a recessed portion [19] formed on a surface of the assembly which allows a user easier purchase of the assembly when inserting or removing the weight selector pin into or from a stem hole. Another embodiment of the assembly comprises CONTROCON rubber dampers [23], and magnets [25] which help hold the start assembly onto the stem of the weight-stack. The start point assembly may be fabricated from a variety of metals or plastics, one being, without limitation, aluminum. A preferred version of the protrusion is fabricated from hardened steel.

FIG. 7 shows a view of the bottom of the preferred embodiment of the terminal limit assembly [17]. The terminal limit assembly comprises a clamping mechanism sized for rigid, but detachable, attachment to a guide rod. The terminal assembly has a main body [27] that forms half of a “C” clamp. The hinged jaw of the clamp [29] is tightened into the main body [27] by turning an adjustment knob [31] with a threaded shaft [33] clock-wise, which screws into a barrel nut [35]. A return spring [37] biases the clamp open as the adjustment knob is turned counter-clockwise. The guide rods of a typical weight-stack are polished, hardened steel. Accordingly, a preferred embodiment of the clamp comprises rubber inserts positioned in both the jaws so to keep the clamp from slipping in use. Rubber bumpers [41] are placed where the weight-stack makes contact with this assembly to minimize the impact forces on it and help to hold it in position. Also shown in this view are the components of an embodiment of the terminal assembly which comprises an audible limit sounding device. When the weight-stack rises to contact the lower surface of the terminal limit assembly, the weight stack contacts a trip-lever [45] of a momentary snap-action switch [43]. This switch allows an electrical current to flow from a miniature battery [47] to a piezo-electric tone generator [49], creating an audible tone. An on-off switch [51] in the circuit may be incorporated to keep the buzzer from being activated when the device is not in use. In certain embodiments, the terminal limiting comprises a radio frequency transmitter operatively connected to the trip lever for wirelessly transmitting performance data.

It should be understand that a clamp is a fastening device to hold or secure objects tightly together to prevent movement or separation through the application of inward pressure the clamp operates for temporarily positioning the terminal weight assembly during operation of the PSSM. The terminal assembly clamp is used to position the assembly temporarily as a range of motion limiting device.

Anything which performs the action of clamping may be called a clamp, so this gives rise to a wide variety of terms across many fields. These are some of the more common ones:

C-clamps are typically made of steel or cast iron, though smaller clamps may be made of pot metal. At the top of the “C” is usually a small flat edge. At the bottom is a threaded hole through which a large threaded screw protrudes. One end of this screw contains a flat edge of similar size to the one at the top of the frame, and the other end usually a small metal bar, perpendicular to the screw itself, which is used to gain leverage when tightening the clamp. When the clamp is completely closed, the flat end of the screw is in contact with the flat end on the frame.

A C-clamp is used by turning the screw through the bottom of the frame until the desired state is reached. In the case that the clamp is being tightened, this is when the objects being secured are satisfactorily secured between the flat end of the screw and the flat end of the frame. If the clamp is being loosened, this is when a sufficient amount of force has relieved to allow the secured objects to be moved.

FIGS. 6 and 7 show, respectively, a top and a bottom view of an embodiment of the terminal limit assembly [53]. This assembly has a main body [53] that forms half of a “C” clamp. The hinged jaw of the clamp [29] is tightened into the main body [53] by an adjustment knob [31] with a threaded shaft [33] which screws into a barrel nut [35]. There is a return spring [37] that biases open the clamp as the adjustment knob is turned counter-clockwise. Rubber inserts [39] set into both jaws of the clamp prevent the terminal assembly from slipping when clamped to a guide rod. An embodiment comprises rubber bumpers [41] placed where the weight-stack makes contact with the terminal assembly to minimize the impact forces on it and help to hold it in position. The terminal point assembly may be fabricated from a variety of metals or plastics. One embodiment comprises a clamping mechanism formed from aluminum. Although not limited to the set of dimensions disclosed herein, it is understood that first and second assemblies are dimensioned and shaped for use with pin selectorized strength machines. Accordingly, an embodiment of the device comprises first and second assemblies dimensioned as set forth in FIGS. 8 and 9.

Operation of the Device

The present invention is a two-membered (i.e. two assemblies) range-of-motion control device. The device finds utility with most commercially available pin selectorized weight machines. In particular, the device is used with fitness systems manufactured by Hoist™ Fitness Systems, San Diego and Nautilus™ strength devices.

In use, to establish the start position, the user defines the start point by inserting the protrusion into one of the holes of the stem mechanism, thereby defining the limit of vertical travel of the stem mechanism, and determining the beginning point of exercise.

Once the start point has been established, an appropriate load of weight plates situated below the top weight plate of the stack may be pinned into operative connection with the stem mechanism. The load to the exerciser is limited by the number of pin holes in the stem mechanism used to establish the start point. Accordingly, if the start point is determined to be three pin holes down below the top plate, then the maximum weight that can be utilized on the stack is three plates from the bottom of the stack.

The terminal ROM limit is achieved by attaching a clamping mechanism onto one of the two guide rods, at the level the user wishes to terminate the movement. In one embodiment, the terminal assembly comprises an piezo electric sound device, which when contacted by the upward movement of the weight plate, triggers a switch positioned on the lower surface of the C-clamp, alerting the patient and clinician that the desired range has been achieved. The audible mode can be disabled with the on-off switch.

The start and terminal ROM limits may be used independently, or in conjunction, dependant on clinical indication.

For exemplary purposes, the above disclosure has detailed the first and second assemblies of the present invention in combination with a weight stack on a pin selectorized weight machine. Likewise, the present invention may be used on other exercise machines where the user rotates an input assembly connected to a cam in tethered connection with a pin-selectorized weight stack. Input assemblies include, but are not restricted to a leg curl machine, or an arm curl machine, a rowing machine, leg press, shoulder press, low back, prone leg curl, lat pull, abdominal, cervical (neck), triceps press, lateral raise, incline press, hip adduction/abduction, torso rotation, pulleys, pectoral, and rear deltoid.

It should be understood that embodiments of the range of motion control device comprise a PSSM. Further the invention is directed to a method of using a PSSM for dosing a range of motion, the method including steps of attaching or engaging the first and second assemblies of the device to a PSSM, and exercising using the PSSM under the control of the range of motion control device.

An embodiment of the invention is directed to a packaged kit which comprises at least one device of the invention (i.e. a start assembly and a terminal assembly). An aspect of the kit further includes one or more pin selectorized strength machines. 

1. A device for controlling range of motion of a stack of weights of a pin selectorized strength machine, said device comprising a. a first assembly sized and dimensioned for laying on the top surface of a weight plate, said first assembly comprising a planar body having a thickness, a protrusion extending from one end of said planar body, said protrusion sized and dimensioned for insertion into a hole of a weight selector stem of a pin selectorized strength machine; b. second assembly comprising a clamping mechanism sized and dimensioned for Attachment to a guide rod of a pin selectorized strength machine.
 2. A method for dosing a range of motion of a pin selectorized strength, said method comprising the steps of a. clamping a terminal limit assembly of a device for controlling range of motion on the guide rod thereby establishing a terminal limit of motion; and b. insertion of the weight selector pin of a start limit assembly of said device into a hole of the weight selection stem mechanism, thereby limiting vertical movement of the weight selector stem mechanism, thereby establishing a start limit of motion, wherein said device comprises ii) a first assembly sized and dimensioned for laying on the top surface of a weight plate, said first assembly comprising a planar body having a thickness, a protrusion extending from one end of said planar body, said protrusion sized and dimensioned for insertion into a hole of a weight selector stem of a pin selectorized strength machine; and (ii) a second assembly comprising a clamping mechanism sized and dimensioned for attachment to a guide rod of a pin selectorized strength machine.
 3. A pin selectorized strength machine comprising a. a first assembly sized and dimensioned for laying on the top surface of a weight plate, said first assembly comprising a planar body having a thickness, a protrusion extending from one end of said planar body, said protrusion sized and dimensioned for insertion into a hole of a weight selector stem mechanism; b. a second assembly comprising a clamping mechanism sized and dimensioned for attachment to a guide rod of said pin selectorized strength machine.
 4. A method for dosing a range of motion of a selected stack of weight plates of a pin selectorized strength machine, said method comprising the steps of: a. clamping a terminal limit assembly of a device for controlling range of motion on the guide rod thereby establishing a terminal limit of motion; and b. insertion of the weight selector pin of a start limit assembly of said device into the hole of the weight selection stem mechanism, thereby establishing a start limit of motion.
 5. A kit comprising at least start assembly and a terminal assembly.
 6. The kit of claim 5 further comprising one or more pin selectorized strength machines. 